Material punch

ABSTRACT

Apparatus for punching material wherein a workpiece is retained in, and transported by, a punching jig. The punching jig has one or more apertures formed therein, these apertures corresponding to the apertures to be punched in said workpiece. A guide plate, having apertures formed therein which correspond in size and position to those of the punching jig, is placed over the workpiece thereby sandwiching the workpiece between the guide plate and the punching jig. A punch-and-die combination is used to punch the desired apertures in the workpiece, the punch and die being aligned with the apertures of the guide plate and the punching jig by approximately locating the jig through use of the guide plate and subsequently fitting the periphery of the die into the appropriate aperture of the jig.

United States Patent George Thomas William Hall Kiikduin, ZH;

Jan Hendrik Sebastiaan Van ljzerloo; Nicolaas A. Althuizen, both of TheHague,

[72] Inventors [54] MATERIAL PUNCH 6 Claims, 41 Drawing Figs.

52 U.S.Cl 83/399,

83/413, 83/454, 83/522, 83/648 51 Int.Cl B23q3/18 50 FieldofSearch83/454,

[5 6] References Cited UNITED STATES PATENTS 3,043.176 7/1962 Johnson eta1. 83/454 X Primary Examiner-F rank T. Yost Attorneys-C. CornellRemsen, Jr., Paul W. Hemminger,

Walter J. Baum, Percy P. Lantzy, Philip M. Bolton, lsidorc Togut andCharles L. Johnson, Jr.

ABSTRACT: Apparatus for punching material wherein a workpiece isretained in, and transported by, a punching jig. The punching jig hasone or more apertures formed therein, these apertures corresponding tothe apertures to be punched in said workpiece. A guide plate, havingapertures formed therein which correspond in size and position to thoseof the punching jig, is placed over the workpiece thereby sandwichingthe workpiece between the guide plate and the punching jig. Apunch-and-die combination is used to punch the desired apertures in theworkpiece, the punch and die being aligned with the apertures of theguide plate and the punching jig by approximately locating the jigthrough use of the guide plate and subsequently fitting the periphery ofthe die into the appropriate aperture of the jig.

PATENTEUJAN 4:972 31,753

SHEET 02 [1F 13 Inventors GEORGE 72 W. HALL JAN H. 5. WW IJZEQLOO -lglAA$ A: HUIZEN y M Attorney PATENTEUJAN M572 3631.753

SHEET 030E 13 Inventors GEORGE r. w. HALL JA N H- 5. WW IJZEELOOlV/COLAAS A. ALTH [ZEN MAV Attorney PATENTEUJAN 41912 31,753

saw our 13 Inventors GEoRGE 7: w, HALL JAN 5, WW ll/ZERLOO N/COLAAS A.ALTHU/ZEN A Home y PATENTEDJAN 41972 3,531,753

sum USOF 13 Inventors GE RGE r. w. HALL \JAIV H- S. VAN IJZEELOO NICLAAS A. ALTHUIZEIV Attorney PATENTEI] JAN 4M2 SHEET 08 [IF 13 o o o o o00 0 1 )0 o o o o oo o 0,

ON ma y Ai m in. M 0 H nW A w NA rm 5&3 A A M n m GMm T PATENTEU JAN41972 SHEET lDUF 13 Inventors GEORGE 73 w. HALL JAN H. 5. V4 IJZEPLOON/COLAAS A. ALTHU/Zf/V Attorney PATENTEDJAN 41972 3,631,753

SHEET 120F 13 Inventors GLORGE 72 W. HALL JAA/ II. S V44! IJZERLOONK'OLAAS A.ALTH [ZEN BYW Attorney MATERIAL PUNCH BACKGROUND OF THEINVENTION The invention relates to a method of and means for punchingmaterial in at least one predetennined position whereby the material tobe punched is fixed to means for transporting the material to thepredetermined position or consecutively to the different predeterminedpositions.

Such a method of punching material, whereby the term punching is definedas the coaction between a punch and a die to pierce, blank or form (or acombination of these operations) material in sheet, bar or striplikeform, is generally known. The material is, in general, firmly clamped orotherwise fixed to a table which is arranged to be moved in twocoordinates to bring the material into the desired position at which itis to be punched. The movement may be effected in any of a number ofwell-known ways, for example by a numerically controlled system or bypreprogramming the movements via a plugboard.

In the manufacture of, for example, sheet metal components thequantities to be produced and the intervals between different seriesplay a major role and in many cases the investment in a numericallycontrolled or programmed machine is not warranted and a drill jig isresorted to, or to positioning of the piece of work with respect to thetool by means of adjustable lineals and locating stops entailingconsiderable separate handlings. The use of these methods of manufactureresults in a production cost that is disproportionately high incomparison to the value of the end product in which the component isassembled. This disproportionately high cost can further increase whereit is not only required to provide a pattern of round holes but also toprovide holes of irregular form or deformations of the material such asindentations, by separate operations on a punchpress or pressbrake.

SUMMARY OF THE INVENTION It is one of the objects of the invention toprovide a method of punching material in one or a number of positionssuch that manufacturing time is reduced considerably over known methodswhere the nature and quantities of the components do not warrant costinvestment in tooling and machines.

According to the present invention this is achieved because the meansconsist of a punching jig with at least one aperture which correspondsto and is coincident with a predetermined position and that the apertureor the apertures can engage with a die whereupon the material may bepunched by a punch coacting with the die.

The invention will be better understood from the following descriptionread with reference to the accompanying drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a simple but typicalcomponent for punching by the method and tools to be described herein;

FIG. 2 shows a punching jig for holding and transporting the componentof FIG. 1;

FIG. 3 shows a guide plate for use with the punching jig of FIG. 2;

FIG. 4 shows a part-sectioned side elevation of the component of FIG. 1located in the punching jig of FIG. 2 with the guide plate of FIG. 3 andready for the effecting of a punching operation;

FIG. 5 shows a simple setup of a punch and die in a punch press forcarrying out a punching operation on the component of FIG. I andemploying the punching jig and guide plate of FIGS. 2 and 3respectively;

FIG. 6 shows a component punched with 12 holes, six of which holes areof a different diameter to the other six;

FIG. 7 shows a punching jig and a guide plate for the punching of thecomponent of FIG. 6;

FIG. 8 shows an arrangement of seven punches and corresponding dies setup in a brakepress for carrying out the method of punching the componentof FIG. 6;

FIGS. 9A-9H, 9J-9N and 9P-9R illustrate various punch apertures whichmay be formed;

FIG. I0 shows the configuration of the extending portion of a die whichis adapted to engage with an aperture in a punching jig;

FIG. 11A shows the die of FIG. 10 in engagement with an aperture in apunching jig in which a component and a guide plate is located;

FIG. [18 illustrates a punch utilized in conjunction with the die ofFIG. 1 1A;

FIG. 12 shows a stripper for a punch and which is color coded toindicate the diameter of the punch;

FIG. 13 shows a die color coded to indicate the diameter plus theclearance allowance for the punching of a certain thickness of material;

FIG. 14 shows a means for counterbalancing the weights (combined) of apunching jig, a component and a guide plate;

FIGS. ISA-15E show a multiposition punching jig for the punching ofcomponents having closely spaced holes of different diameters;

FIGS. 16 and 17 show a means for punching of components with a greatweight;

FIG. 18 shows a component having six groups of holes;

FIG. 19 shows a punching jig for the component of FIG. 18;

FIG. 20 shows a press tool for punching all the holes of a group in thecomponent of FIG. 19 simultaneously;

FIG. 21 shows one method of maintaining the punches of the tool of FIG.20;

FIG. 22 shows another method of maintaining the punches of the tool ofFIG. 20 in fixed relationship in a punch holder.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring in the first instanceto FIG. I this figure shows a simple and typical component which may bepunched with holes at predetermined positions by the method and toolsnow to be described herein. In this case the component I comprises amild steel plate of rectangular form and measuring 300 mm. by mm. by 2mm. thick. This particular component is required to be punched at 20predetermined positions with holes 2 each of 6-mm. diameter.

FIG. 2 shows a punching jig 3 for holding and transporting the componentI of FIG. 1 to effect the punching at the predetermined positions. Itcomprised a plate of traylike form preferably of a lightweight materialsuch as aluminum having two end portions 4 bent to form handgrips bywhich the operator can move it, with the component, from onepredetermined punching position to another and so on. Four right-angledmembers 5 are rivetted or otherwise affixed to the tray portion andthese serve to prevent movement of the component with respect to aseries of holes which extend through the tray and the centers of whichholes are coaxial with the centers of the holes to be punched in thecomponent I at the predetermined positions. The holes 6 in the tray areall of like diameter and which diameter permits them to be engaged by adie of the punching tool in a manner to be later described.

FIG. 3 shows a guide plate associated with the punching jig 3 of FIG. 2.This guide plate 7 has precisely the same rectangular form and the widthand breadth dimensions of the component l but is somewhat thinner, say 1mm. The purpose of the guide plate is to give the operator an indicationof when the punching jig is approximately in a position in which aparticular hole in the tray of the punching jig 3 can be engaged by thepreviously mentioned die. The relationship between the component 1, thepunching jig 3 and the guide plate 7 when cooperatively assembled tocarry out punching operations is shown in FIG. 4. In this figure it willbe seen that the component 1 is sandwiched between the punching jig 3and the guide plate 7.

FIG. 5 shows a punch 8 mounted in a punchholder 9 for operation in thedirections indicated by the arrows A" and 8" under the action of the ram10 of a conventional punch press (not shown). The punch 8 accommodatesthereon a well-known type of stripper" 11 of hard plastic and having thepurpose of stripping material or a component off the punch after apunching operation has been carried out. Arranged for coaction with thepunch 8 to effect punching of the component is a die 12, in thisparticular instance the die 12 is circular in form and may constitute anintegral part of a dieblock 13 or function as a separate integer whichmay be fitted into the die-block 13 as a loose item. In any case the die12 is arranged to extend vertically above the upper surface of thedie-block 13 by an amount which is substantially equal to the thicknessof the material from which the punching jig 3 is made, the uppermostperiphery of the die 12 is chamfered at approximately 45 at the positiondesignated by the reference numeral 14. The diameter of the verticallyextending portion of the die 12 is such that it is slightly smaller, sayby 0.05 to 0.1 mm. than the diameter of the holes 6 in the punching jig3. The engagement of the extending portion of the die 12 in one of theholes 6 in the punching jig 3 is seen in FIG. 5. It will also be notedthat the under surface of the component 1 rests on the upper surface ofthe die 12. It is in these relative positions of the assembled punchingjig 3, the component I and the guide plate 7 with respect to the punch 8and the die 12 that a punching operation is carried out. The consecutivepunching of all the holes 2 in the component 1 is a matter of locatingthe punching jig 3 in successive punching positions, and each of whichpredetermined positions is determined by the engagement of the die 12 ina hole 6 of the tray portion of the punching jig 3.

Referring now to FIG. 6 this figure shows a component 15 which isrequired to be punched with 12 holes, six of which are of alike diameterand the other six of which are each different in diameter from eachother. The holes of like diameter are designated by the reference letterC and the holes of different diameter are designated by the referenceletters "D, E, F," G, H and l." FIG. 7 shows a punching jig l6 and guideplate 17 for the punching of the different sizes of holes in thecomponent 15. The punching of the different holes in component 15 in anormal punch press would necessitate seven different changes of punchsuch as 8 and respective dies such as 12, to carry out these changes forevery different diameter of hole to be punched per component 15, or topunch all components one after another with one size of punch and dieand so on for other sizes of punch and die would be time wasting andindeed would nullify any advantages gained by the use of this method. Toeliminate such time-wasting setups it is proposed herein to employ awellknown type press brake in which all the required punches andrespective dies can be set up side by side, and by which means all theholes of different diameters in a component such as 15 may be punchedone after another without the necessity of either changing punches ordies or removing the component from the punching jig 16.

FIG. 8 shows a set up of seven punches and their respective dies forpunching the holes of different diameter in the component 15. For thesake of clarity the punches and respective dies have been designated bythe same reference letters as the corresponding holes in the component15 to be punched and the punching jig 16. In this instance the dies areloose items which are mounted in a common die-block 18 while thecorresponding punches are mounted in a conventional manner in thevertically operable ram 19 of the brakepress. Plateaus such as 20 arerigidly affixed to the opposite sides of the dieblock 18 to support thepunching jig 16 with its respective guide plate 17 carrying thecomponent 15 during the punching operations. The punching jig 16 withcomponent 15 and guide plate 17 are located in the first punchingposition and in which position the six holes C" of the same diameter arepunched (the term first punching position as used here defines the firstof the seven positions along the common die-block at which punching isto take place).

The method and tools herein described are not confined to the punchingof holes of circular form, and various forms of holes which may bepunched are shown in FIGS. 9A-D:

square, rectangular, triangular, oval and elongated holes withsemicircular ends. Material or a component may be part punched also toprovide lips which extend outwardly from a surface or punched to provideindentations as shown in FIGS. 9E, 9F, 9G, 9H, 9], 9K and FIGS. 9L, 9M,9N, 9?, and 9R which are top and front views, respectively. In the casesof holes of square, rectangular, triangular, oval or elongated, orindeed irregular configuration it is necessary to ensure that the jigand component cannot be rotated in the horizontal plane when located ina punching position otherwise the orientation of the hole, indentationor lip with respect to the component will be incorrect. To prevent thisoccurring that portion of the particular die in use and which extendsabove the surface of the die-block is either square or rectangular inform as shown in FIG. 10 and indicated by the reference numeral 2];similarly the corresponding hole in a jig in use of like form. Thus whena die of such form is in engagement with a corresponding hole in apunching jig the latter and the component is prevented from rotation.FIG. 11A shows a part-sectioned pictorial view of the die 21 mounted ina die-block 23 and engaging a correspondingly shaped hole 24 in apunching jig 2S accommodating a component 26, which component issandwiched between the punching jig 25 and a guide plate 27. The punch 8and its stripper 11 is shown in FIG. 115.

In order to simplify the setting up of punches and corresponding dies asdesignated C" to I inclusive in FIG. 8 the respective strippers 11 ofFIG. 5 are coded with three peripheral bands of color. The color of thewidest of the three bands denoting the diameter of the punch in tens ofmillimeters, the next widest denoting the diameter of the punch in wholemillimeters and the narrowest band denoting the diameter of the punch intenths of a millimeter. FIG. 12 shows the widths of the bands of coloron a stripper and which bands are designated 28, 29 and 30 respectively.

Such a color code may be as follows:

con-Jovian:-

Examples Punch diameter l0s of mm. Units of mm. tenths of mm.

22.2 mm, Dark blue Dark blue Whole stripper colored dark blue) YellowRed Light blue Dark blue Dark green Y ellow Black Light green Dark brownLight brown Such a system can also be applied to the color coding of thedies corresponding to punches, and to the guide plates of punching jigs,whereby an operator is easily able to identify which punch is to be setup with a particular corresponding die. He is further able to identifythe position of a hole, or holes, to be punched by corelating the colorcoding of the stripper(s) of the punch(es) with the color coding of thehole(s) in a guide plate. In the case of the color coding of dies anextra color position may be required to indicate a particular requiredclearance between a punch and a die. In general it may be said that thediameter of a hole in a die is greater than the diameter of acorresponding punch by 5 percent of the material thickness to be punched(such a clearance may vary for particular classes of accuracy requiredin the final hole diameter and the material to be punched). Dies may becolor coded to indicate their diameters with clearance by providing fourindentations in the upper surface of ever-decreasing diameter. Thelargest diameter of indentation filled with a color indicating thediameter of the punch in tens of millimeters, the next largestindicating the diameter of the punch in whole millimeters, the nextlargest indicating the diameter in tenths of a millimeter and thesmallest indentation indicating the clearance. The sizes of suchindentations in a die 12 are shown in FIG. 13, the largest to thesmallest indicated by the reference numerals 32, 33, 34 and 35.

The combined weights of a punching jig, the component and a guide platemight be considerable and cause operator fatigue through the necessityto lift these combined weights every time it is necessary to move thepunching jig and its contents from one punching position to another. Inorder to overcome this a punch press such as illustrated in FIG. 14 anddesignated by the reference numeral 36 may have a frame such as 37fitted and from the horizontal member 38 of which two well-known typesof balancer 39 are fitted. These balancers house each a cable such as 40which by spring means is held in a wound-up condition within the casingof the balancer. The tension with which the cable may be maintained inthe wound-up condition may be adjusted by a key 41. These balancers havecable tensions that can be adjusted between wide limits. For example,the tension of certain types can be adjusted so that a pull of anywherebetween I and kilos is required (according to the adjustment) to unreelthe cable out of the casing of the balancer. This tension can be used tocounterbalance the weight of the punching jig 3, the component l and theguide plate 7. Two hooks 42 are affixed to the free ends of the cablesand these are arranged to engage in holes drilled in the handles 4 ofthe punching jig 3. The angles which the cables make with respect to thecasings of the balancers 39 and the punching jig 3 are such thatirrespective of the position of the punching jig 3 with respect to thepunch 8 and its stripper 11 these cables are free from the possibilityof fouling the punch press.

Closely spaced holes in a component could give rise to dimensionalinaccuracies between the centers of such holes due to breakthrough ofone aperture in the punching jig into another aperture. With areasonably experienced operator using the jig to carry out punchingoperations, a 90 peripheral engagement of a round aperture in a punchingjig with a corresponding round die is sufiicient to ensure accuratepunching of a component. Any lesser degree of peripheral engagementcould possibly lead to misalignment between the punching jig and a dieand thus to dimensional inaccuracies between the centers of holespunched in a component. To anticipate this undesirable result amultiposition punching jig is employed such that with a componentaccommodated in the punching jig in one of the positions certain holesmay be punched in the component via apertures in the punching jig whichdo not break through into each other, and such that when the componentis accommodated in another position in the jig other holes which areclosely spaced to the first punched holes may be punched via apertureswhich also do not break through into each other.

If reference is now made to FIG. A there is shown a component 60 havinga large hole 61 encompassed by four closely spaced smaller holes 62. InFIG. 158 there is shown a part ofa punching jig 63 with four apertures64 for the punching of the four previously mentioned small holes, whichbreak through into a center aperture 65 for the punching of thepreviously mentioned large hole 61. It will be seen that sufficientperipheral engagement of the large center hole with a corresponding diewill obtain, but in the case of the four apertures 64 which breakthrough" to the center aperture 65 there may not be sufficientperipheral engagement with a corresponding die and thus the possibilityexists that dimensional inaccuracies between the centers of holes willresult through misalignment between apertures in the punching jig andcorresponding dies.

In FIG. 15C there is shown a two-position punching jig 66 with acomponent 60 in each half. The large hole 61 in the component may bepunched when the component is accommodated in the left-hand half of thepunching jig and the jig illustrated at FIG. ISD is utilized, and thecomponent is punched with the four smaller holes 62 when it isaccommodated in the right-hand half of the punching and the jigillustrated at FIG. 15E is utilized. When using such a punching jig witha press brake with a set up of two punches, one for the large hole 61and one for the small holes 62, it will be possible to load the punchingjig 66 with two similar components and then punch the large hole 61 inone component 60 and the four smaller holes 62 in the other component,after which the positions of the two components may be changed andpunching of the other holes therein may be carried out.

It is self-evident that punching jigs with more than two positions canbe employed when necessary in view of very closely spaced holes to bepunched in a component.

Assisted lifting and movement of a punching jig, a component and a guideplate by the employment of balancers has already been described. Incertain circumstances the combined weights of these items may be suchthat it is inconvenient to employ balancers and more convenient to movethe punching jig and its contents by means of roller tables at each sideof the press. In such cases the necessity to lift the punching jig andits contents may be obviated by arranging for the upper surface of thedie to lie in the same plane as the bed of the press until the punchingjig has been located in such a position that on raising the die it willseek the appropriate aperture in the punching jig. If the periphery ofthe extending portion of the die is either chamfered or radiused acertain amount of misalignment, between the die and an aperture, themisalignment will be taken up through the action ofthe die, in itsvertical movement upward, engaging the peripheral edge of an aperture inthe punching jig so that it is forced laterally into alignment. It istherefore proposed that the die should be raised just prior to effectingthe punching operation and that punching is inhibited until there isfull and proper engagement between the aperture in the punching jig andthe die.

This principle is further shown in FIG. 16. A punching jig 98 with acomponent 99 to be punched and a guide plate 100 rest on the bed 73 of apress. The misalignment of the die 67 and the aperture 101 is indicatedwith M. The bed contains two pistons 91 and 92 which both extend abovethe upper surface 74 of the bed under the action of a spring and whichcan be depressed under the action of the weight of the punching jig, thecomponent and the guide plate. In the depressed situation each pistoncloses a switch. Moreover, the die closes a third switch in its upperposition. The punching press is arranged in such a way that only whenthe three switches are closed can a punching operation be carried out.

FIG. 17 shows the situation whereby the punching jig with its contentsis lifted by the die. So in this situation it is impossible to carry outthe punching operation.

Certain components may have several groups of holes. A group of holes ina component constitutes a punching position therein and by utilizing themethods described herein and adapted tools, groups of holes in a numberof punching positions can be punched consecutively. FIG. 18 shows acomponent 1 12 having six groups of holes. These holes, total three pergroup, are designated by the reference numbers 109, and 111. In thisinstance the component 112 is 3 meters long and 30 centimeters wide andis of 3-millimeter mild steel. The holes 109, 110 and 111 are of 6, l2and 18 millimeters diameter respectively.

FIG. 19 shows a punching jig 113 for the component 112. Two endsportions 114 are bent to form handles and similarly extending portions,115 to inclusive, from opposite sides are also bent to form handles.Other portions 122 of the two opposite sides are sharply bent to formupturned side portions by which means the component 112 is maintainedimmovable with respect to the punching jig 113 in the width coordinate.The component 112 is maintained immovable in the length coordinate bytwo strips 123 which are spot welded to the punching jig 113. The guideplate 124 has the same width and length dimensions as the component butis somewhat thinner, i.e., 1 millimeter. The punching jig 113 and theguide plate 124 are both punched to provide apertures which are coaxialwith the holes in the component 1 12 which are to be punched.

The tool shown in FIG. 20 includes a die set comprising a bolster 12Sand a punchholder 126, the latter of which is guided in its movementrelative to the former by two pillars 127 which run in bearings 128. Thedies 129, 130 and 131 for punching the holes 109, 110 and 111 in thecomponent 112 are fitted directly into counterbored holes, correspondingto the group of holes to be punched, in the bolster 125. A partcross-sectioned view of the positions of the dies 129, 130 and 131 inthe bolster 125 and the positions of the corresponding punches 132, 133and 134 in the punch holder are shown in FIG. 21, together with theassociated strippers for the punches. The punches 132, 133 and 134 areaffixed and maintained in the punch holder 126 in counterbored holes bythreaded bushes 135 having axial slots 136 by which means they may bescrewed in the punchholder 126. These bushes are rendered shakeproof bya well-known liquid-type synthetic adhesive for metals. Alternatively,and as shown in the part-sectioned view of FIG. 22 by a well-known typeof epoxy-resin filling 137 poured in the counterbored holes around theshanks and heads of the punches 132, 133 and 134. This type of punchfixing is more suitable for punches required to effect light punchingoperation.

We claim:

1. Apparatus for punching material comprising:

a punching jig for retaining and transporting said material, said jigbeing formed with at least one aperture therein;

a guide plate provided with at least one aperture which is similar toand coincident with said at least one jig aperture, said material beinglocated between said punching jig and said guide plate;

a punch and die aligned with said jig and guide plate apertures forpunching said material, said jig aperture being engaged by said die toalign said punch and die and wherein the upper periphery of said dieextends through said jig aperture and the undersurface of said materialrests on the upper surface of said die; and

means for controlling said punch and die as as to allow a punchingoperation only when said upper periphery of said die extends throughsaid jig aperture.

2. Apparatus for punching material, according to claim 1, wherein theupper periphery of said die is chamfered so as to facilitate engagementbetween said die and jig aperture.

3. Apparatus for punching material, according to claim 1, wherein saidcontrol means comprises a switch which is activated by contact betweensaid under surface of said material and the upper surface of said die.

4. Apparatus for punching material, according to claim 1, wherein theupper periphery of said die which engages said jig aperture is shaped soas to provide a desired rotational orientation between said die and saidmaterial.

5. Apparatus for punching material, according to claim 4, wherein saidpunch, said die and said guide plate apertures are color coded withrespect to size.

6. Apparatus for punching material comprising:

a punching jig for retaining and transporting said material,

said jig being formed with at least one aperture therein;

a guide plate provided with at least one aperture which is similar toand coincident with said at least one jig aperture, said material beinglocated between said punching jig and said guide plate;

means aligned with said jig and guide plate apertures for punching saidmaterial; and

means for supporting and moving said punching jig, said guide plate andsaid material, said supporting and moving means comprising;

a frame; two balancers coupled to said frame; and

cables connecting said balance to said punching jig, said supporting anmoving means counterbalancmg the weight of the punching jig, thematerial and the guide plate, thereby facilitating movement thereof.

1. Apparatus for punching material comprising: a punching jig forretaining and transporting said material, said jig being formed with atleast one aperture therein; a guide plate provided with at least oneaperture which is similar to and coincident with said at least one jigaperture, said material being located between said punching jig and saidguide plate; a punch and die aligned with said jig and guide plateapertures for punching said material, said jig aperture being engaged bysaid die to align said punch and die and wherein the upper periphery ofsaid die extends through said jig aperture and the undersurface of saidmaterial rests on the upper surface of said die; and means forcontrolling said punch and die as as to allow a punching operation onlywhen said upper periphery of said die extends through said jig aperture.2. Apparatus for punching material, according to claim 1, wherein theupper periphery of said die is chamfered so as to facilitate engagementbetween said die and jig aperture.
 3. Apparatus for punching material,according to claim 1, wherein said control means comprises a switchwhich is activated by contact between said under surface of saidmaterial and the upper surface of said die.
 4. Apparatus for punchingmaterial, according to claim 1, wherein the upper periphery of said diewhich engages said jig aperture is shaped so as to provide a desiredrotational orientation between said die and said material.
 5. Apparatusfor punching material, according to claim 4, wherein said punch, saiddie and said guide plate apertures are color coded with respect to size.6. Apparatus for punching material comprising: a punching jig forretaining and transporting said material, said jig being formed with atleast one aperture therein; a guide plate provided with at least oneaperture which is similar to and coincident with said at least one jigaperture, said material being located between said punching jig and saidguide plate; means aligned with said jig and guide plate apertures forpunching said material; and means for supporting and moving saidpunching jig, said guide plate and said material, said supporting andmoving means comprising; a frame; two balancers coupled to said frame;and cables connecting said balancers to said punching jig, saidsupporting and moving means counterbalancing the weight of the punchingjig, the material and the guide plate, thereby facilitating movementthereof.